A conventional sunroof driving device disclosed in JP2005-240851A includes a cross-connecting member establishing connection between respective front ends of a pair of rail members and a driving device arranged at the cross-connecting member. The driving device includes a drive motor and a spur wheel to which rotation of the drive motor is transmitted via reduction gears. The driving device is configured to transmit the rotation of the drive motor to the spur wheel, so that two rack belts engaging with the spur wheel are pulled in and out from casings accommodating the respective rack belts. Accordingly, slide members to which the rack belts are connected, respectively, slide along the respective rail members. Consequently, the driving device is configured so as to operate a movable panel provided at a roof opening portion formed in a vehicle roof.
As described above, the rack belts are accommodated in the respective casings so as to be pulled therein and therefrom. The rack belts provided at front and rear sides in a vehicle longitudinal direction engage with the spur wheel of the driving device. The casings extending along the total length of the cross-connecting member are provided at drive sides and at release sides of the rack belts, respectively. Accordingly, the cross-connecting member at which the driving device is arranged, requires space used for arranging the rack belts and the casings accommodating the rack belts, thereby increasing the sunroof driving device in size in vehicle longitudinal direction.
A need thus exists for a sunroof driving device, which is not susceptible to the drawback mentioned above.